TLR9 and systemic lupus erythematosus: Moreover, these splenic DCs in disease mice displayed heightened TLR7- and TLR9-mediated responses, as indicated by the elevated expressions of the B cell-stimulating cytokine IL-10 and chemoattractant CXCL13, with the latter also being critical for Tfh migration into B cell follicles for GC formation during lupus pathogenesis.